Downstream interference suppression in full-duplex communications

Abstract

An apparatus includes a transmitter, a receiver and a combining element. The transmitter includes multiple coupling devices coupled to a coaxial network via multiple respective ports, and is configured to transmit multiple transmit signals via the coupling devices, and to receive from the coaxial network via the multiple coupling devices multiple reception signals. The receiver is configured to receive a combined signal of the multiple reception signals, interfered by multiple respective interfering signals that originate from the multiple transmit signals, and to process the combined signal to recover data carried in the reception signals. The combining element, included in at least one of the transmitter and the receiver, is configured to receive the multiple reception signals from the respective couplers, and to generate the combined signal with a suppressed level of the interference signals by setting at least a phase of at least one of the reception signals.

The invention claimed is: 
     
       1. A transceiver, comprising:
 a transmitter coupled to a coaxial network via multiple coupling devices, the transmitter configured to transmit to the coaxial network, via the multiple coupling devices, multiple respective transmit signals that are split from a common signal; and 
 a receiver, configured to:
 receive, via the multiple coupling devices, multiple respective reception signals that are interfered by respective leakage signals caused by local leakage of the transmit signals in the transceiver; 
 generate from the multiple reception signals a combined reception signal having a suppressed level of the local leakage of the transmit signals, by combining the multiple reception signals with one another while a leakage signal in at least one of the reception signals has a reversed phase relative to the leakage signal in another of the reception signals; and 
 process the combined reception signal to recover data carried in the multiple reception signals. 
 
 
     
     
       2. The apparatus according to  claim 1 , wherein the leakage signals are caused by leakage of the respective transmit signals to the receiver at least via the respective couplers, and wherein the receiver is configured to suppress the leakage signals by exploiting a coherency among the leakage signals inherited from the transmit signals. 
     
     
       3. The apparatus according to  claim 1 , wherein the receiver is configured to generate the combined reception signal by combining the multiple reception signals in pairs, wherein the reception signals of each pair are combined with a 180 degree phase shift using a respective anti-phase combiner. 
     
     
       4. The apparatus according to  claim 1 , wherein the receiver comprises multiple compensation elements that compensate for path differences among the reception signals, by setting each compensation element with one or more signal parameters selected from a list comprising a phase parameter, a gain parameter and a delay parameter of a respective reception signal, prior to combining. 
     
     
       5. The apparatus according to  claim 4 , wherein the receiver is configured to adaptively modify a setting of the compensation elements in an attempt to minimize a level of the leakage signals. 
     
     
       6. The apparatus according to  claim 5 , wherein the receiver is configured to monitor a performance level of the receiver, and to adjust the setting of the compensation elements based on the monitored performance level. 
     
     
       7. The apparatus according to  claim 1 , wherein the transmitter is configured to generate the multiple transmit signals in a digital domain of the transmitter, and to set signal parameters of the reception signals by setting the signal parameters of the respective transmit signals in the digital domain of the transmitter. 
     
     
       8. The apparatus according to  claim 7 , wherein the transmitter is configured to select a signal parameter to set in a transmit signal from a list comprising a phase parameter, a gain parameter and a delay parameter. 
     
     
       9. The apparatus according to  claim 7 , wherein the transmitter is configured to modify the signal parameters of the transmit signals, based on monitoring a performance level of the receiver. 
     
     
       10. The apparatus according to  claim 1 , wherein the receiver is configured to receive first and second reception signals that are interfered by respective first and second leakage signals having mutually-coherent phases, and to generate the combined reception signal by combining the first and second reception signals, including reversing a phase of the first reception signal and not reversing a phase of the second reception signal. 
     
     
       11. The apparatus according to  claim 1 , wherein a first leakage signal of the first reception signal and a second leakage signal of the second reception signal are caused by respective first and second transmit signals transmitted with anti-phase relative to one another, and wherein the receiver is configured to coherently combine the first and second reception signals. 
     
     
       12. A method, comprising:
 transmitting to a coaxial network, via multiple coupling devices of a transmitter, multiple respective transmit signals that are split from a common signal; 
 receiving in a receiver, via the multiple coupling devices, multiple respective reception signals that are interfered by respective leakage signals caused by local leakage of the transmit signals in a transceiver comprising the transmitter and the receiver; 
 generating from the multiple reception signals a combined reception signal having a suppressed level of the local leakage of the transmit signals, by combining the multiple reception signals with one another while a leakage signal in at least one of the reception signals has a reversed phase relative to the leakage signal in another of the reception signals; and 
 processing the combined reception signal to recover data carried in the multiple reception signals. 
 
     
     
       13. The method according to  claim 12 , wherein the leakage signals are caused by leakage of the respective transmit signals to the receiver at least via the respective couplers, and wherein generating the combined reception signal comprises suppressing the leakage signals by exploiting a coherency among the leakage signals inherited from the transmit signals. 
     
     
       14. The method according to  claim 12 , wherein generating the combined reception signal comprises combining the multiple reception signals in pairs, wherein the reception signals of each pair are combined with a 180 degree phase shift using a respective anti-phase combiner. 
     
     
       15. The method according to  claim 12 , and comprising compensating for path differences among the reception signals by setting one or more signal parameters, to be applied by respective compensation elements prior to combining, wherein the one or more signal parameters are selected from a list comprising a phase parameter, a gain parameter and a delay parameter of a respective reception signal. 
     
     
       16. The method according to  claim 15 , and comprising adaptively modifying a setting of the compensation elements that determines the signal parameters applied to the reception signals by the respective compensation elements, in an attempt to minimize a level of the leakage signals. 
     
     
       17. The method according to  claim 16 , and comprising monitoring a performance level of the receiver, and adjusting the setting of the compensation elements based on the monitored performance level. 
     
     
       18. The method according to  claim 12 , and comprising generating the multiple transmit signals in a digital domain of the transmitter, and setting signal parameters of the reception signals by setting the signal parameters of the respective transmit signals in the digital domain of the transmitter. 
     
     
       19. The method according to  claim 18 , wherein setting the signal parameters of the transmit signals comprises selecting a signal parameter to set in a transmit signal from a list comprising a phase parameter, a gain parameter and a delay parameter. 
     
     
       20. The method according to  claim 18 , and comprising modifying the signal parameters of the transmit signals, based on monitoring a performance level of the receiver. 
     
     
       21. The method according to  claim 12 , wherein receiving the reception signals comprises receiving first and second reception signals that are interfered by respective first and second leakage signals having mutually-coherent phases, and wherein generating the combined reception signal comprises combining the first and second reception signals, including reversing a phase of the first reception signal and not reversing a phase of the second reception signal. 
     
     
       22. The method according to  claim 12 , wherein a first leakage signal of the first reception signal and a second leakage signal of the second reception signal are caused by respective first and second transmit signals transmitted with anti-phase relative to one another, and wherein generating the combined reception signal comprises coherently combining the first and second reception signals.